This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Proposed research addresses questions of morphological evolution of novel feeding structures in plant parasitic nematodes within a phylogenetic context. Comparative, high resolution TEM reconstruction from thin sections is essential for interpreting morphological evolution. High pressure freezing and freeze substitution have been proven to be optimal and superior to any other known approach for preservation of nematode ultrastructure. On this basis, access to the Bal-Tec HPM 010 High Pressure Freezing Machine at NCMIR is requested.